and  y = x³these curve meet  when  x³ = √x       =>  x = 0  or  1y = √x  is higher than  x³  between x= 0 and x = 1.areas under the curves / enclosed by the curves :==============================at any x, the radius of the circular cross section of the paraboloid is y..Volume of an infinitesimal  volume of a disc of radius y  and  thick ness   dx       = π y²  dx   the equation of the curve is     y = √x      or  x =  y²Volume of the paraboloid :=====================R = 50.0 ft  A = 2 π / 3 radians = 120 deg. = 2π/3 radians Height raised by, when the wheel turns by 90 deg.  =  1 radius. = 50 ft.           as the person is at the level of the center of the wheel.height raised by, when the wheel turns by 30 deg more =  R Sin (2π/3 - π/2) = R/2 = 25 ft.The height above the ground = 25 + 50 = 75 feet..======================ANGULAR speed = ω = angle turned / time DURATION = [ 2 π /3 ] / 30 sec              = π / 45  radians / sec              = 0.0698 radians / sec